1. Field of the Invention
The present invention relates to a hydraulic-power piping unit accommodated in a load-handling lift truck having a truck body and a full free lift upright assembly so as to provide a hydraulic connection between a control valve unit mounted on the truck body and a hydraulic actuator for an attachment mounted on a lift bracket member of the full free lift upright assembly.
2. Description of the Related Art
In a load handling lift truck, specifically, a lift truck having a full free lift upright assembly, it is known to use a hydraulic-power piping unit for providing a hydraulic connection between a control valve unit mounted in a truck body and a hydraulic actuator for a load handling attachment mounted on a free lift bracket which is constructed to be vertically moved by a free lift cylinder disposed in the full free lift upright assembly. The known hydraulic power piping unit has a hose reel on which hydraulic flexible hoses for supply and return of hydraulic power are supported so as to be able to move together with the free lift bracket. The hose reel is attached to an outer part of the full free lift upright assembly. For example, U.S. Pat. No. 3,552,425 to Harlan D. Olson discloses a hose reel of a hydraulic power line takeup unit located outwardly from a mast assembly arranged at the front of a lift truck. The outside location of the hydraulic power piping unit, however, contains a certain disadvantages in that when the free lift upright assembly is in an at-rest or non-lift position, the hose reel is close to an overhead guard of the lift truck body resulting in an extremely restricted backward tilt motion of the free lift upright assembly. The outside location of the hydraulic power piping unit also has other disadvantages in that the hose reel, a rotary joint device, and the pipes and hoses of the hydraulic power piping unit are apt to be damaged due to the probability of their coming into contact with objects in the vicinity of the lift truck, and that this position of the unit entails a considerable loss of hydraulic head.